Arrow broadhead

ABSTRACT

An improved broadhead arrowhead is disclosed including spiral-shaped, curving or twisting, blades of increasing width along a leading edge thereof, and an insert including a bearing element which allows for broadhead rotation independent of the arrow shaft about the longitudinal axis of the arrow shaft during flight. The curved blades and bearing element of the present invention allow the broadhead to continue rotating after contacting the target.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The inventor hereof claims the benefit of U.S. provisional patent application serial No. 60/283,679 filed Apr. 12, 2001 and U.S. provisional patent application serial No. 60/333,902 filed Nov. 28, 2001.

FIELD OF THE INVENTION

[0002] The present invention relates generally to arrowheads for use in bow-and-arrow target shooting and hunting; and, more particularly, to an improved broadhead-type arrowhead having superior flight and performance characteristics achieved through the use of spiral blades of increasing width. In alternate embodiments, the use of a bearing element in association with a broadhead provides for independent broadhead rotation with respect to the arrow shaft.

BACKGROUND OF THE INVENTION

[0003] The use of a bow and arrow in lieu of a rifle, shotgun, or the like, in the hunting of game has become increasingly popular in recent years. Many of the game hunters practicing bow and arrow hunting have found the use of a broadhead-type arrow achieves more efficient results, particularly in the hunting of relatively large game. The usual presently available broadhead-type arrow has certain disadvantages in that the speed, distance, and the accuracy of flight of the arrow shaft through the air is frequently adversely affected by the structural configuration of the arrowhead. In addition, there are certain legal requirements setting forth the conditions under which the use and structure of the broadhead-type arrows must comply.

[0004] Many attempts have been made to solve the problems encountered with the use of the broadhead-type arrow, such as shown in the Chandler U.S. Pat. No. 2,289,284, issued Jul. 7, 1942, and entitled “Interchangeable Arrowhead;” Recker U.S. Pat. No. 2,753,643, issued Jul. 10, 1956, and entitled “Fishing Arrow;” Grissinger U.S. Pat. No. 2,937,873, issued May 24, 1960, and entitled “Hunting Head for an Arrow or the Like;” Richter U.S. Pat. No. 2,940,758, issued Jun. 14, 1960, and entitled “Arrowhead;” Yurchich U.S. Pat. No. 3,014,305, issued Dec. 26, 1961, and entitled “Arrowhead for Bow Fishing;” Swails U.S. Pat. No. 3,036,396, issued May 29, 1962, and entitled “Retractable Arrow;” McKinzie U.S. Pat. No. 3,138,383, issued Jun. 23, 1964, and entitled “Dual Purpose Arrow Head;” Lint U.S. Pat. No. 3,168,313, issued Feb. 2, 1965, and entitled “Hunting Arrowhead with Retractable Barb;” and Hendricks U.S. Pat. No. 3,600,835, issued Aug. 24, 1971, and entitled “Spear Head with Swingable Barb.” Other configurations are also known.

[0005] Most prior art broadheads have straight blades, in-line with the arrow shaft, and rotate fixedly with the arrow shaft in flight until they come in contact with the target. When in contact with the target, they are forced to stop spinning and cut straight through the target with no rotation. This reduces the efficiency of the cutting action.

[0006] Accordingly, it would be advantageous to provide a broadhead-type arrowhead having superior flight and performance characteristics achieved through the use of spiral-shaped, curving or twisting, blades of increasing width along a leading edge. It would be further advantageous to provide a broadhead-type arrowhead for use in association with a bearing element to provide independent broadhead rotation with respect to the arrow shaft.

SUMMARY OF THE INVENTION

[0007] In summary, the present invention relates to an improved arrowhead design which includes spiral-shaped, curving or twisting, blades of increasing width along a leading edge thereof, and which may include the use of an insert comprising a bearing element to allow for the broadhead-type arrowhead to be supported at the end of an arrow shaft; yet, to be rotatable relative to that shaft, the rotation being substantially along the longitudinal axis of the shaft. Such characteristics allow the broadhead to rotate at a differing rate during flight from the arrow shaft rotation; and, further, upon impact with the target, allow the broadhead to continue in its rotation to penetrate a substantial distance into the target. Such characteristics are facilitated by the spiral-shaped, or twisting, nature of the blades. The above characteristics are provided without the broadhead becoming detached or partially unscrewed from the insert. An alternate embodiment comprises spiral-shaped, curving or twisting, blades and a rotating bearing with the added characteristic that the blades may be replaceable.

[0008] Accordingly, the present invention overcomes deficiencies in prior art broadhead arrowheads by providing an improved arrow broadhead in accordance with the disclosure herein.

[0009] It is, therefore, an object of the present invention to provide an improved arrow broadhead.

[0010] It is a further object of the present invention to provide an improved arrow broadhead which includes improved cutting characteristics.

[0011] It is a still further object of the present invention to provide an improved arrow broadhead which includes improved flight characteristics.

[0012] It is yet a further object of the present invention to provide an improved arrow broadhead which includes improved accuracy characteristics.

[0013] These and other objects are accomplished by the improved arrow broadhead disclosed herein and will become apparent to the reader from a review of the following Detailed Description of Preferred Embodiments in conjunction with the accompanying drawing Figures in which like numerals designate like elements.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Having thus described the invention in general terms, reference will now be made to the accompanying drawing Figures, which are not necessarily drawn to scale, and wherein:

[0015]FIG. 1 is a side view of a one piece broadhead of the present invention showing the point, blades, shaft, and threads;

[0016]FIG. 2 is an end view of the broadhead of the present invention taken from the tip and showing the blades, tip, chisel flats, and aerodynamic cut-out areas;

[0017]FIG. 3 is an end view of the broadhead of the present invention taken from the arrow shaft toward the direction of flight;

[0018]FIG. 4 is a sectional view of the insert and bearing assembly of the present invention which allows the broadhead to rotate independently of the arrow shaft;

[0019]FIG. 5 is an exploded perspective view of the insert and bearing assembly of the present invention showing the rear portion of the broadhead, along with an embodiment of the bearing assembly and arrow shaft;

[0020]FIG. 6 is a side view of an alternate embodiment of the broadhead of the present invention showing the shaft of the broadhead, tip, and groove;

[0021]FIG. 7 is a side view of the alternate embodiment of the broadhead of FIG. 6 showing a removable blade, lug, and hook; and,

[0022]FIG. 8 is a partial side view of the alternate embodiment of the broadhead of FIG. 6 showing one blade and the retainer.

[0023] It is to be noted that the Figures presented are intended solely for the purpose of illustration and that they are, therefore, neither desired nor intended to limit the invention to any or all of the exact details of construction shown, except insofar as they may be deemed essential to the claimed invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.

[0025] Referring now to FIGS. 1-3, in a preferred embodiment, broadhead 10 is formed as an integral unit. Broadhead 10 comprises tip 12 which is pointed on the end and which, optionally, may have a plurality of chisel flats 20 or which may simply be conical in shape. Tip 12, shaft 30, journal 40, threads 50, and blades 60 may be formed as one integral unit. Blades 60 are also preferably formed as one piece with shaft 30 and the other previously mentioned elements.

[0026] Blades 60 comprise cutting edges 65. The cutting width of blades 60 is small near tip 12 and gradually increases rearwardly toward threads 50 along a leading edge of the blade, as taken in view of the direction of flight. Maximum cutting width may be achieved at the rearmost portion of blade 60, or may be achieved intermediate the blade length.

[0027] Blades 60 have a spiral, curved, or twisted shape, curving from front to rear, approximately the same pitch as the average fletchings on most arrows. The curve will promote true flight by imparting a rifling aerodynamic to the broadhead. Each of blades 60 preferably includes cut relief 70, and has an aerodynamic cut-out area 80, both of which reduce the weight and aerodynamic drag of broadhead 10. Broadhead 10 preferably has at least two blades 60, with three such blades being preferred.

[0028] With reference to FIGS. 6-8, in an alternate embodiment, shaft 130 provides undercut 144 immediately adjacent the rear of point 12. Shaft 130 also has a plurality of equally spaced grooves 140, parallel to the axis of flight and equal to the number of blades 180 used. IQ Blades 180 provide hook 150 in their forward end, hook 150 being of suitable configuration such that undercut 144 will retain the forward end of blades 180. Inboard edge 155 of blades 180 fit into groove 140. The rear end of blades 180 has a protruding lug 160, which is configured so that retainer 170 may snap over lug 160 and, thereby, hold blades 180 to shaft 130.

[0029] Blades 180 share many features with the embodiment of FIGS. 1-3, including, but not limited to: a spiral-shaped, or twisting, curve of increasing width from front toward rear along a leading edge thereof, tip 12 comprising optional chisel flats 20, threads 50, journal 40, cut relief 70, and aerodynamic cut-out area 80. With the configuration of this embodiment, blades 180 may be quickly and easily replaced in the field.

[0030]FIGS. 4 and 5 illustrate a feature designed to be used with any broadhead, whether of prior art configuration or of the configuration of the several embodiments of the present invention.

[0031] By way of background, standard inserts are designed to be glued into a tublular arrow shaft. Such inserts have internal threads, so that all types of practice and hunting tips can be used and interchanged. Once the tips have been screwed into the insert, the tips are stationary. Once the arrow is in flight, the tips can only rotate as the arrow rotates.

[0032] Advantageously according to one embodiment of the present invention, insert 100 comprises sleeve element 190 which is substantially cylindrical in shape, and which carries flanged portion 200 at one end thereof. Flanged portion 200 has a diameter slightly greater than the substantially smooth outer diameter of sleeve element 190. The outer cylindrical surface of sleeve element 190 fits within the tubular end of arrow shaft A, preferably glued therein in much the same manner as a conventional insert would be inserted and glued. Flanged portion 200 provides a “stop” against the front end of arrow shaft A.

[0033] Bearing element 210 is inserted within sleeve element 190. Sleeve element 220 is inserted within bearing element 210. Sleeve element 220 carries internal threads 225 which allow threads 50 of broadhead 10 to threadably fasten thereto.

[0034] In order to screw broadhead 10 into sleeve element 220, it is necessary to temporarily “fix” sleeve element 220 relative to sleeve element 190. This can be done by providing holes 230 in sleeve element 220 and sleeve element 190 as needed, such that pin 240 can be used to prevent relative rotation.

[0035] As an example, sleeve element 220 might carry two holes 230, disposed for cooperating with two holes 230 carried by flanged portion 200 of sleeve element 190. Once sleeve element 190 is glued into arrow shaft A, the user would align holes 230, and place pin 240 into holes 230 in order to hold bearing element 210 stationary. In this manner, the user can tighten broadhead 10 into sleeve element 220.

[0036] Once so affixed, insert 100 allows arrow shaft A and broadhead 10 to spin at differing relative rates of rotation during flight and, also, allows broadhead 10 to continue spinning after impact with a target. Such configuration, further, allows the arrow to fly with more accuracy, and allows broadhead 10 to penetrate the intended target more effectively.

[0037] When any type of broadhead, and especially the broadhead of the present invention, is used with the insert 100, improved flight characteristics will be achieved. As a further advantage, the user will not have to adjust bow sights as often, because of truer flight.

[0038] Bearing element 210 may comprise needle or ball-type bearings, with internal {fraction (8/32)} TPI to fit all arrows. It will be apparent to those ordinarily skilled in the art that sleeve bearings, sintered metal bearings, simple clearance and lubrication arrangements, or the like could also be used within the contemplation of the present invention. Without regard to the specific type of bearing selected, the application and advantages thereof remain the same. It is noted as a design constraint, however, that the bearing should not allow a large relative longitudinal movement between the arrow shaft and the arrowhead.

[0039] The insert assembly configuration of the present invention preferably will fit all arrow shaft sizes and, preferably, will glue into the arrow as do conventional inserts known in the art. The benefit of the new insert assembly of the present invention is that once the arrowhead has been screwed into the insert assembly, it is able to rotate in either direction without becoming unscrewed. The insert assembly of the present invention also accommodates different broadhead designs and fletching pitches during flight.

[0040] Broadhead 10, in one embodiment, preferably is made of titanium or other suitable metallic material, and is cast or otherwise formed as an integral unit, so as to be stronger and more durable than other broadheads currently on the market. Preferably, broadhead 10 will weigh approximately 100 to 125 grains, such weight being the most popular amongst hunters.

[0041] Additional modifications and other embodiments of the invention may become apparent to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. It is to be understood, however, that the invention is not to be limited to the specific embodiments disclosed. It is further to be understood that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation. 

I claim:
 1. An improved broadhead arrowhead for affixation to an arrow shaft comprising: (a.) a forward portion comprising a point; (b.) a rearward portion for engaging said arrow shaft; (c.) a curved blade intermediate said forward and rearward portions, said curvature promoting a twisting aspect of said broadhead with regard to a direction of flight; (d.) said blade increasing in width along a leading edge thereof.
 2. The broadhead of claim 1 wherein said forward portion further comprises chisel-shaped flats.
 3. The broadhead of claim 1 wherein said blade further comprises a cut-out portion.
 4. The broadhead of claim 1 wherein said rearward portion further comprises a thread.
 5. The broadhead of claim 1 wherein said rearward portion further comprises a journal.
 6. The broadhead of claim 1 further comprising means for allowing said broadhead to rotate independently of said arrow shaft.
 7. The broadhead of claim 6 wherein said means for allowing said broadhead to rotate independently of said arrow shaft comprises a bearing element.
 8. The broadhead of claim 6 wherein said means for allowing said broadhead to rotate independently of said arrow shaft comprises a plurality of sleeves accommodating relative rotational motion therebetween.
 9. The broadhead of claim 1 further comprising means for replacement of said blade independently from the remainder of said broadhead.
 10. The broadhead of claim 9 wherein said means for replacement of said blade comprises a lug at a rearward portion of said blade and a retainer for cooperating with said lug.
 11. The broadhead of claim 9 wherein said means for replacement of said blade comprises a groove for accommodating said blade.
 12. An improved arrow comprising: (a.) a broadhead arrowhead comprising a forward portion carrying a point, a rearward portion for engaging a shaft of said arrow, and a blade intermediate said forward and rearward portions; and, (b.) means for accommodating independent rotation of said broadhead arrowhead with regard to said arrow shaft.
 13. The arrow of claim 12 wherein said blade is a curved blade, said curvature promoting a twisting aspect of said broadhead with regard to a direction of flight of said arrow.
 14. The arrow of claim 12 wherein said means for accommodating independent rotation of said arrowhead comprises a bearing element.
 15. The arrow of claim 12 wherein said means for accommodating independent rotation of said arrowhead comprises a plurality of sleeves allowing relative rotational motion therebetween.
 16. The arrow of claim 12 wherein said blade may be separated independently from the remainder of said broadhead for replacement of either said blade or said remainder.
 17. An improved arrow comprising: (a.) an arrowhead, said arrowhead comprising a pointed tip at a forward end thereof, and a threaded portion at a rearward end thereof; and, (b.) an insert, said insert comprising an outer portion for engaging an inner portion of an arrow shaft, an internally threaded inner portion for engaging said arrowhead threaded portion, said insert outer and inner portions accommodating relative rotation therebetween.
 18. The arrow of claim wherein said arrowhead comprises a broadhead arrowhead.
 19. The arrow of claim 18 wherein said broadhead comprises a curved blade of increasing width along a leading edge thereof.
 20. The arrow of claim 17 wherein said insert comprises a bearing. 